Bag closing apparatus



' Dec. 31,1963 I A. F. PETERSON BAG CLOSING APPARATUS 2 Sheets-Sheet 1 Filed April 24', 1961 Z INVENTOR Axe/ F PZIZ/"JOn ATTORNEY Dec. '31, 1963 A. F. PETERSON BAG CLOSING APPARATUS H 2 Sheets-Sheet 2 l 4 4 m 5 W9 a 5 w l l a w 5 2 1 Z 7;. 5 m Z fl w m 3 1 w. 4 p 6 2 A 3 4 5 6 w l. M57 F n 6 F 64 1 5 W4 Axel f. Pe/ersdn United States Patent 3,115,736 BAG CLGSXNG APPARATUS Axel E. Peterson, 594-0 Pleasant Ave, Minneapolis, Minn. Filed Apr. 24, 1961, Ser. No. 104,889 8 Claims. (Cl. 5337 1) This invention relates to an improvement in bag closing apparatus and deals particularly with an apparatus for folding the open end of a bag into a flat folded position so that it may be stitched or otherwise sealed.

An object of the present invention resides in the provision of a bag closer which includes a pair of guide belts which engage the sides of the filled bag and hold the bag centered with respect to the conveyor upon which it rides. As the bag reaches bag closing position, it strikes a gate which is mounted over the conveyor and in the path of movement of the bag. This gate acts to straighten the bag vertically, and to stop movement of the conveyor with the ovular top of the bag in proper position to be closed.

A feature of the present invention resides in the provision of a pair of fixed fingers which may be lowered into position outwardly of the bag and centered on opposite sides of the bag. The apparatus also includes two pairs of fingers which are mounted at opposite ends of a lazy tong structure having a fixed central axis. These bags are arranged to be lowered into the interior of the bag and lit within the ovular opening of the bag. By moving the outermost pivots of the lazy tong arrangement away from the fixed center pivot, the four fingers pivot toward each other and at the same time the fingers at opposite sides of the bag move apart so as to form a central gusset fold about the fixed fingers.

A further feature of the present invention resides in the provision of upwardly and inwardly inclined pressure plates which are urged against the upper portion of the bag as the fingers fold the bag opening. These pressure plates act to urge the material within the bag into proper form so that the tendency for the bag opening to return to its original ovular shape is eliminated.

A further feature of the present invention resides in the provision of a pair of guide rails which are protected inwardly after the bag has been folded to prevent the re opening of the bag, and to guide the flattened bag end to a sewing machine or other bag sealer as soon as the gate is released and the conveyor moved to advance the closed bag.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of the specification.

FIGURE 1 is a perspective view of the bag closing apparatus showing the general arrangement of parts thereon.

FIGURE 2 is a perspective View of a closed bag.

FIGURE 3 is a diagrammatic view showing the manner in which the guide belts are driven.

FIGURE 4 is a perspective view of the finger mechanism in readiness to be lowered to the bag.

FIGURE 5 is an end elevational view of a detailed portion of the apparatus.

FIGURE 6 is a diagrammatic view of the finger mech anism showing the manner in which this mechanism acts to fold the open end of the bag.

FIGURE 7 is an end elevational view of a portion of the bag at the completion of the folding operation.

FIGURE 8 is a diagrammatic view of the control mechanism for controlling the operation of the apparatus.

As indicated in FIGURE 1 of the drawings, the bag closing apparatus A includes a base It which supports a pair of parallel upright standards 11. The base 10 is designed to extend beneath a conveyor which is indicated 3,1153% Patented Dec. 31, 1963 diagrammatically at 12 and which acts to carry the bags from the filling apparatus to the bag stitcher or other sealing means. The standards 11 extend on one side only of the conveyor so that the entire apparatus may be moved into or out of position without disturbing the conveyor.

An inverted U-shaped body frame, which is indicated in general by the numeral 13, is supported by the standards 11. The frame 13 includes a rear frame side 14, a front frame side 15, and a connecting top portion 16. The rear side 14 0f the frame 13 is provided with a pair of parallel vertical split sleeves 17 which encircle the upper ends of the standards 11. The split sleeves are provided with pairs of cars 19 on opposite sides of the split, and clamping bolts 26 are provided to clamp the sleeves in proper position upon the standards. As the entire bag closing mechansim is mounted upon the frame 13, the apparatus may be easily and quickly adjusted to accommodate bags of various heights.

A folding finger assembly 21 is supported by a vertical rod 22 slidaoly supported to extend through the frame top 1-6 for vertical siidable movement of the finger assembly. The upper end of the rod 22 is pivotally connected at 23 to a lever arm 24 which is pivoted intermediate its ends at 25 to a fulcrum link 26. The fulcrum ink 26 is pivotally connected at 27 to a lug 29 on the top frame portion 16. As the axes of the pivots 23, 25 and 27 are parallel, the finger assembly supporting rod 22 may move vertically the fulcrum link 26 swinging slightly to compensate for variations in angularity.

A pneumatic cylinder 39 is pivotally supported at 31 to a yolk 32 projecting from the side 15 of the frame 13. The piston within the cylinder 3%) is connected by a piston rod 33 to a clevis 34 which is pivotally connected at 35 to the end of the lever 24. Movement of the piston within the cylinder 34 thus acts to raise and lower the finger assembly.

With reference now to FIGURE 4 of the drawings, the rod 22 is connected to a right angularly extending arm 36 which serves as a slide shaft for a pair of sleeves 37 and 39 which may be keyed to the shaft to prevent relative rotation. Each of the sleeves 37 and 39 support an L- shaped bracket including a vertical arm 40, 41 and an inwardly extending horizontal arm 42, 43 respectively. The base of a cylinder 44 is connected to the vertical arm suspended from the sleeve 39, and the piston within the cylinder 44 is provided with a connecting rod 45 which extends through the vertical arm 41 suspended from the sleeve 37 and is anchored thereto by nuts 4-6. Movement of the piston within the cylinder 44 thus moves the sleeves 37 and 3? away from one another, or toward one another.

A curved arm 47 extends downwardly from the cross rod 36, this arm skirting the cylinder 4d and supporting a vertical pivot 49 which is axially aligned with the sup porting rod 22. The horizontal arms 42 and 43 of the brackets suspended from the sleeves 3'7 and 39 are also provided with downwardly extending parallel pivots 5t} and 51. The fixed pivot 49 and the movable pivots 50 and 51 support a lazy tong arrangement which will be described.

The fixed pivot 49 pivotally supports a pair of parallel lever arms 52 and an intermediate lever arm 53. One end of the parallel levers 52 is pivotally connected at 541 to the bifurcated end of a lever arm 55 which is pivctally supported intermediate its ends on the pivot 51 movable with the sleeve 39. The other end of the parallel levers 52 is pivotally connected at 56 to the bifurcated ends of a lever arm 57 which is pivoted intermediate its ends to the pivot 54) movable with the sleeve 37. One end of the intermediate lever 53 is pivotally connected at 59 to a lever arm 6%} which is pivotally supported intermediate its ends upon the pivot 51. The other end of the lever 53 is pivotally connected at 62 to a lever arm 9 d which is pivotally supported intermediate its ends pivot d. The outer ends of the lever arms 55, 57, 61) and 63 are provided with downwardly projecting fingers 64, 65, 66 and 67 respectively. The lower end of each of these fingers is preferably rounded and bent to incline downwardly and toward the axis of the center pivot -19.

Split clamps 69 and 7d are mounted "on the opposite ends of the cross rod 36 and act to support vertically extending fingers 71 and 72 respectively. The outer ends of the fingers 71 and 72 are preferably rounded and are bent downwardly and outwardly away from the axis of the central pivot 49. Clamping bolts '73 and '74 are provided extending through the split ends of the clamps and 71 to hold the 1i gers 71 and 72 in adjusted posinon.

In the operation of this portion of the apparatus, the filled bag B is delivered into position below the finger assembly 21 with the upper open end of the bag in generally ovular form. The finger unit 21 is lowered while in the general position illustrated in FIGURE 4 of the drawings, the fingers 6d, 65, 66 and 67 extending downwardly into the interior of the bag, and the fingers 71 and 72 extending exteriorily of the bag. Fluid is then introduced into the cylinder 44, moving the sleeves 37 and 39 outwardly toward the ends of the supporting rod. The fingers then swing the portions of the top of the bag which they engage gradually inwardly, the movable fingers extending outwardly beyond the fixed fingers 71 and 72. As a result, the fixed fingers 71 and 72 form a gusset fold on each side of the bag, and the opposed edges of the bag are closely adjacent to one another.

Means 'are provided for properly shaping the bag and its contents as the fingers fold the upper end of the bag. As indicated in FIGURES 5 and 7 of the drawings, a pair of downwardly and outwardly diverging pressure plates 76 and 77 engage opposite sides of the bag B simultaneously, and act to force the contents of the bag into the proper shape to permit the folding of the bag. When the bag is filled with flour or other powdered or granular material, the upper surface of the product is usually substantially flat, or the product may be piled to a greater depth at one side of the bag or the other, or at one end of the bag or the other. By providing the inclined pressure plates 76 and 77, the bag is forced into the proper shape to be closed, and the product within the bag is moved into the proper shape to permit the bag to be closed and sealed. The pressure plates 76 and 77 are urged inwardly against the bag simultaneously with the pivoting of the folding fingers so that as the pressure plates urge the contents of the bag into the proper form, the fingers fold the top of the bag in a manner to form the 'gussets at opposite sides of the bag.

As may be seen in FIGURES l and 6 of the drawings, the plate 76 is supported by a piston rod 79 connected to a piston within a horizontal cylinder 86 supported by the frame side 14. The plate 76 is held in horizontal position by a pair of rods 81 secured to the rear of the pressure plate 76 and extending through suitable bearings 82 on the frame side 14. The pressure plate 77 is similarly connected to a connecting rod 83 which is attached to a piston within a cylinder 84 connected to the frame side 15, the cylinder being horizontal and in opposed relation to the cylinder 80. The pressure plate 77 is stabilized by a pair of rods secured to the pressure plate and extending rearwardly therefrom in a direction parallel to the axis of the piston rod 83. The stabilizing :rods 85 extends thuough bearings 86 on the frame side 15.

The apparatus also includes a pair of guide rails 87 and 89 which are slidably supported on opposite sides of the finger assembly 21 for movement toward and away from the folded upper end of the bag B. The rail 87 is operated by a piston rod 911 which is connected to a piston within a horizontal cylinder 91 mounted on the frame on the 4 side 14. The rail 89 is stabilized by means of stabilizing rods 92 which extend through bearings 93 on the frame side 14. The guide rail 87 is similarly supported by a piston rod 9 1 connected to a piston within the cylinder 95. The rail 89 is also connected to stabilizing rods 96 which extend through bearings 97 of the frame side 15.

The bags B on the conveyor 12 are centered with respect to the bag closing mechanism by the locating belts 3% and 1011 which are designed to engage opposite sides of the bag below the level of the fill within the bags. The belts 99 and 1% are supported by brac.;ets 1111 and 1112 which are secured to the lower edges of the frame sides 14 and 1S. Idler pulleys 103 and 1134 are supported on vertical pivots 1 315 and 1116 respectively at the entrance end of the belts and at the ends of the brackets 1&1 and 102. As is diagrammatically illustrated in FIG- URE 3 of the drawings, pulleys 1137 and 1119 support the outlet ends of the belts 99 and 1%, these pulleys similarly being supported by the brackets H11 and 162. The pulleys 1d"? and 1139' are mounted upon vertical shafts 111D and 111 which extend upwardly in parallel relation. A motor 112 acts through a drive chain or belt 113 to drive a gear reducer 114 having an outlet sprocket 115 connected to a similar sprocket 116 on the shaft 110 by a suitable chain 117. The shaft 111) is connected to a gear box 117 by a chain 119, the outlet sprocket 12(9- of the gear box meshing with a gear 121 on the shaft 111 so as to rotate the shaft 111 at the same speed as the shaft 110 but in the opposite direction. As a result, the inner reaches of the belts 99 and 1 311 rotate in the same direction and parallel to the conveyor 112 so as to guide the bags into proper position.

A gate indicated in general by the numeral 122 is mounted over the conveyor 12 and is centered with respect thereto. The gate 122 includes a pair of space vertical abutments 123 designed to engage the bag B on opposite sides of the center thereof so as to hold the bag erect. The abutments 123 tend to move the bag into vertical position upon the conveyor 12. In other words, if the bag is tilting forwardly or rearwardly, the vertically extending abutments '123 tend to swing the bag into vertical position.

The gate is pivotally supported by a bracket 124- which is slidably supported on a horizontal arm 125 adjustable longitudinally of the conveyor belt 112. The bracket 124 includes a vertical pivot 126 which pivotally supports an arm 127 upon which the vertical abutments 123 are mounted. The gate 122 incorporates a switch which is operated as each bag engages the gate, the purpose of the switch being to stop the operation of the conveyor 12, and to initiate a cycle of operation of the bag closing mechanism. While the details of construction of this switch are not shown, it should be understood that the switch comprises merely a limit switch which functions when a bag moves against the gate to open the circuit to the motor driving the conveyor 12 and to close the circuit to the bag closing apparatus A which acts to close the bag.

As is diagrammatically illustrated in FIGURE 8, gate 127 is moved from operative position overlying the conveyor 12 to inoperative position to one side of the conveyor 12 by operation of a piston within a cylinder 129. The cylinder 1251 is pivotally connected at 130 to the frame of the apparatus forming a part of the bracket 125, and the piston in the gate 12, is connected by a piston rod 131 to the cylinder 127 through a pivotal connection 132. As the piston is retracted in the cylinder 129, the cylinder swings about its axis through approximately 90. This action operates to release the switch previously described, opening the circuit to the bag closing apparatus after it has completed one cycle of operation, and closing the circuit to the conveyor 12 so as to move the bag which has been closed to a sealing position.

The manner of opeartion of the bag closing apparatus is diagrammatically illustrated in FIGURE 8 of the drawings. A motor 133 acts through a drive chain 134 or similar connection to a gear reducer 135. The output of the gear reducer 135 is connected by chains or belts 136 and bevel gears 137 to drive a cam shaft 139. The cam shaft 139 includes a pair of single cams 140 and 141, and a pair of double cams 142 and 143. The purpose of the double cams 142 and 143 is to provide a means of adjusting the cams. The cams 142, 140, 143 and 141 respectively cooperate with valves 144, 145, 146 and 147. In the construction illustrated, the cams are used to control the flow of air to the various cylinders. However it is obvious that the valves mentioned could operate hydraulic cylinders if preferred.

The valve 144 is connected by conduits 149 and 150 to one end of each of the cylinders 30 and 84. Thus, when the valve 144 is actuated, the cylinder 30 is operated in a manner to lower the finger assembly 21 into the open top of the bag. Simultaneously, the air in the cylinder 84 (and also the cylinder 83) act to move the pressure plates 76 and 77 inwardly against the bag.

As soon as the finger assembly 21 has been lowered sufiiciently to enter the top of the bag, the cam 140 operates the valve 145 which directs air through a conduit 151 to an end of the cylinder 44, tending to move the sleeves 37 and 39 apart upon the supporting shaft 36. Thus, as the pressure plates 76 and 77 are moved inwardly against the top of the bag, the finger folds the top of the bag outwardly on opposite sides of the fixed fingers 71 and 72, forming a gusset fold at each end of the bag.

The cam 143 then operates the valve 146 which directs air through a conduit 152 to the cylinder 95, and the guide rails 87 and 89 are moved inwardly. As the guide rails 87 and 89 move inwardly a distance sufiicient to prevent the reopening of the bag, the cam 142 releases the valve 144, permitting air to flow through the conduit 153 to the finger raising and lowering cylinder 30, and through a conduit 154 to the pressure plate operating cylinder 84. The flow of air into the cylinders 30 and 84 acts to raise the finger assembly 21 and simultaneously to retract the pressure plates 76 and 77. When the guide rails 87 and 89 are in place on opposite sides of the folded end of the bag, the cam 141 operates the valve 147 to direct air through the conduit 155 to the cylinder 129, retracting the piston in this cylinder, and swinging the gate 127 out of engagement with the bag upon the conveyor 12. At the same time, the circuit is opened to the motor of the conveyor 12, and the sack is advanced through the sealing mechanism, not shown in the present drawings.

As subsequent steps of the operation, the cam 143 releases the valve 146 permitting a flow of fluid through the conduit 156 to the cylinder 95, acting to retract the guide rails 87 and 89 after the bag has been advanced by the conveyor 12. The cam 141 also releases the valve 147 permitting the flow of fluid through the line 158 to the cylinder 129, which acts to swing the gate 123 back into obstructing position above the conveyor 12. At any point after the finger assembly 21 has been elevated out of engagement with the bag by the cylinder 30, the cam 140 releases the valve 145, permitting the flow of fluid through the conduit 157 to the cylinder 44, which moves the sleeves 37 and 39 toward the center of their support, swinging the various folding fingers into the position illustrated in FIGURE 4 of the drawings.

In accordance with the patent statutes, I have described the principles of construction and operation of my improvement in bag closing apparatus, and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that changes may be made Within the scope of the following claims without departing from the spirit of my invention.

I claim:

1. A bag closing apparatus including a lazy-tong structure including a central pair of crossed links pivoted intermediate their ends, a fixed pivot connecting said links, a second pair of links connected to each of the ends of the central links, each second pair of links being pivotally connected intermediate the ends thereof and including folding fingers projecting in generally parallel relation from the free ends thereof, said fingers being adapted to extend into the open end of a bag, a pair of fixed fingers arranged on a plane through the axes of the pivots and adapted to lie outwardly of the open end of a bag, and means for moving the pivots connecting said second pairs of links apart, said movement swinging said folding fingers of each pair toward one another outwardly of said fixed fingers.

2. The structure of claim 1 and including means slidably supporting the pivots connecting each second pair of fingers.

3. A bag closing apparatus including a finger assembly, said assembly including a cross arm, a central pivot connected to the center of said cross arm, a pair of slides slidably supported on said cross arm for movement toward or away from the center thereof, outer pivots on said arms parallel to said central pivot, a central pairs of links pivoted intermediate their ends to said central pivot, an outer pair of links pivoted intermediate their ends to each of said outer pivots, pivots connecting the ends of said central links to the inner ends of each outer pair of links, folding fingers projecting in generally parallel relation to each of the outer ends of said outer pair of links, and a pair of stationary fingers secured to said cross arm and projecting therefrom in parallel relation to said folding fingers, and means for moving said slides toward and away from the center of said cross arm, each pair of said folding fingers being swingable from a widely spaced position inwardly of said fixed fingers to a closely spaced position outwardly of said fixed fingers.

4. The structure of claim 3 and including means supporting said finger assembly for vertical movement.

5. The structure of claim 3 and in which said means for moving said slides comprises a cylinder connected to one slide and a piston in said cylinder connected to the other of said slides.

6. A bag closing apparatus including a finger assembly, said assembly including a cross arm, a pair of fixed parallel fingers secured to said cross arm near opposite ends thereof, a pair of slides supported on said cross arm for movement toward and away from the center thereof, a central pivot on said cross arm generally parallel to said fingers, linkage pivotally connected to said central pivot and to said slides, and pairs of movable fingers supported by said linkage in generally parallel relation to said fixed fingers, said linkage supporting said movable fingers from wirely spaced position inwardly of said fixed fingers to closely spaced position outwardly of said fixed fingers upon movement of said slide toward and away from the center of said cross arm.

7. The structure of claim 6 and including means for supporting said finger assembly for vertical movement.

8. The structure of claim 6 and including expansible and contractable means for moving said slides.

References Cited in the file of this patent UNITED STATES PATENTS 1,841,051 Podel Jan. 12, 1932 1,851,676 Litchfield Mar. 29, 1932 2,243,805 Knapp May 27, 1941 2,624,995 Allen Jan. 13, 1953 2,947,904 Focht Aug. 2, 1960 

1. A BAG CLOSING APPARATUS INCLUDING A LAZY-TONG STRUCTURE INCLUDING A CENTRAL PAIR OF CROSSED LINKS PIVOTED INTERMEDIATE THEIR ENDS, A FIXED PIVOT CONNECTING SAID LINKS, A SECOND PAIR OF LINKS CONNECTED TO EACH OF THE ENDS OF THE CENTRAL LINKS, EACH SECOND PAIR OF LINKS BEING PIVOTALLY CONNECTED INTERMEDIATE THE ENDS THEREOF AND INCLUDING FOLDING FINGERS PROJECTING IN GENERALLY PARALLEL RELATION FROM THE FREE ENDS THEREOF, SAID FINGERS BEING ADAPTED TO EXTEND INTO THE OPEN END OF A BAG, A PAIR OF FIXED FINGERS ARRANGED ON A PLANE THROUGH THE AXES OF THE PIVOTS AND ADAPTED TO LIE OUTWARDLY OF THE OPEN END OF A BAG, AND MEANS FOR MOVING THE PIVOTS CONNECTING SAID SECOND PAIRS OF LINKS APART, SAID MOVEMENT SWINGING SAID FOLDING FINGERS OF EACH PAIR TOWARD ONE ANOTHER OUTWARDLY OF SAID FIXED FINGERS. 